This function validates objects of S4-class
BTCADR. Hereby, checks are conducted
with respect to the first character of the addresses;
their consistency with the net version and
the correspondence of the checksums.
validBtcAdr(object)BTCADR object
Bernhard Pfaff
Other BtcAdresses: BTCADR-class,
PrivKey2PubKey, PrivKey2Wif,
PubHash2BtcAdr,
PubKey2PubHash, Wif2PrivKey,
base58CheckDecode,
base58CheckEncode, concatHex,
createBtcAdr,
createPrivateKey, decodeHex,
hash160, hash256